Abstract
The expression pattern of cytokeratins (CKs) varies with epithelial cell type. However, the expression of many different CKs has not been clearly defined in ameloblastomas. We used cytokeratins (CK) 1, 4, 6, 7, 10, 10/13, 15, 16, 17, 19, 20 and AE1/AE3 monoclonal antibodies and polyclonal keratin (PK) antibody to elucidate the localization of these CKs in ameloblastomas by immunohistochemistry. Biopsy and operative specimens of 31 ameloblastomas, of which 13 were follicular and 18 plexiform, were used in the present study. CK8, CK19, AE1/AE3 and PK were positive in all follicular (100%) and plexiform (100%) patterns of ameloblastomas. Although CK8 and CK19 are present in simple epithelium, they were observed in the inner cells of tumor nests of ameloblastomas. CK13 was also positive in all metaplastic epithelium of follicular patterns (100%) and was positive in plexiform patterns (56%). CK6, CK7, CK15, CK16 and CK17 positive rates were 54%, 8%, 23%, 46% and 54% in follicular patterns, and 22%, 17%, 0%, 0% and 11% in plexiform patterns, respectively. CK1, 4, 10 and 20 were negative in all both follicular and plexiform patterns. These results indicate that CK15 and CK16 tend to be more specific positive in follicular than in plexiform ameloblastomas.
